Preliminary findings of soft yaw concept

As wind turbines increase in size and the demands for lifetime also increases, new methods of load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and hence dampen the loads to the system. This paper presents work previous done on this subject with foucus on hydraulic yaw systems. By utilizing the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine studies shows that a significant reduction in fatigue loads to the yaw system and rotor shaft is possible by the soft yaw drive concept.